Process of dyeing wool.



UNITED STATES oFFIoE.

HOMER WINSLOW, F PROVID EI TCE, RHODE ISLANDKASSIGNOR TO CASSELLA COLOR COMPANY; OF NEW YORK, N. Y.

rnoonss or DYEIN'G WOOL."

No Drawing.

To all ohom it may concern:

Be it known that I, HOMER Wmsnow, a citizen of the United States, residing at 37 Messer-street, Provid'encc,-in the county of Providence and St-ateof Rhode Island, have invented a new and useful Process of Dyeing? \Vool, according to the following specification. l As is well known, the dyeing of wool with adjective, mordant, or lake forming dyes, consists, essentially, in forming upon and within the fiber color lakes of the dyestuffs with metallic oxids. producing color lakes upon the fiber are in general use, of which may be mentioned: the

impregnating of the material with a solution of the salts of chromic acid or chromic oxid, aluminum or iron salts, usually in the presence of, certain. organic or inorganic acids, from which solutions hydroxids of the metal are deposited upon and within the fiber. The material thus treated is then passed into the solution of a suitable dye, when a color lake is formed by the union of the dye with the metallic oxid reviously fixed upon the fiber. A modification of this method is to first impregnate thematerial with the dye, which is withdrawn from its solution, and absorbed by the fiber, in the presence of acids, or acid salts. The metallic salt is then added, usually to the samebath,-but sometimes to a subsequent one, when the color lake is formed as before. Potassium and sodium bichromate are the most important metallic salts used for thispurpose, and may be taken as typical ones for the reactions stated.

Certain of the adjective dyes do not immediately form color lakes in the presence of metallic salts. This fact'has been taken advantage of to still further modify and to greatly simplify the process of dyeing, in that the metallic salt and the dyestuif may now be added together to the same bath,- when in the presence of organic acids, or

their acid salts, or neutral salts of ammonium whichare easily dissociatedby boiling. It is to this latter method of dyeing that my invention is ap lied. M I have now iscoveredtthat when the salts cf magnesium or those of the calcium group (if metals, calcium, barium and strontium, are added to the d ebath, together with suitable dyes, and a c romate or chromium salt, the dyeing of wool and other animal fibers is Specification of Letters Patent.

Several methods for greatly facilitated; the, material is very evenly and uniformly dyed; and the resulting color is fuller, richer in tone, and, with many dyes, more permanent.

The reaction which takes place in the dye bathbetween the magnesium salt, or a saltof the calcium group of metals,the dyestufi','and the chr omate or chromium salt is not fully determined, but is probabl as follows Weak color lakes are formed by the salts of magnesium and by those of the calcium group of metals-with the dyestufl', which combine with and build up those formed 'by the rinci al metallic salt, greatly enhancing its va ue. The acid liberated from the base of the salt is made available to accelerate the dyein H The dyeing operation may be demonstrated by making up a dyebath with a suitable dyestufi, potassium or sodium b1- chromate, and a quantity of magnesium sulfate,.'e ual to about twice the quantity; of dyestu used. The material is entered, the bath heated, andgboiling continueduntil tHe dyeing is completed .Besides magnesium sulfate other magnesium salts and the salts of calcium, barium and strontium act more or less favorably.

Patented Nov. 30, 1909. Application filed December 19, 1908. Serial No. 468,347.

Example I; To the dyebath containing aboi1t400 gallons of water add 2 lbs. anthra cene chromate brown EB, lb. bichromate of otassium (or sodium), 4 lbs. magnesium sul ate. 100 lbs. of wool, yarn, or pieces are entered into the bath at to deg.. F., the bath is heated, and boiling continued one to-two hours.- Example II: To the dyebath of 400 gallons water. add: 2 lbs. anthr'acene chromate F., heat, and boil one half hour, then add reen B, 4 lbs. magnesium sulfate. Enter 1. lbpbichromate of potassium or sodium,

and boil one half to one hour lon er. Ad-

ditions of dye for the purpose o shading may be made to the dyebath at any time.

By acid chrome dyes as herein mentioned, are meant dyes such as are referred to, for instance, in the December, 1907, page 420, or in the Tea:- tz'le Colorist for May 1909 and. October Claims. Y

1. The process of dyeing animal fibers- Tewtz'le .World Record of" salts of alkaline earths, ente the goods In witness whereof I have hereunto signed '10 to be dyed into the solution, an boilin the my name this seventh day of December liquor until the color is fixed upon the her. 1908, in'the presence of two subscribing wit- 2. The process of dyeing animal fibers nesses. v 5 which consists in preparin' a solution of anacid chrome dye, salts of c romic acid, and' 4 I HOMER I salts of magnesium, entering the goods to be Witnesses dyed into the solution, and boiling the liq- GILMAN E. Jorr,

uor until the color is fixed upon the fiber. GEORGE S. LINCOLN. 

